There is a sleight of hand that happens in news articles, political debates, and family arguments: a speaker lays out a list of facts and then, without anyone noticing, slips in a demand about what you must do. This episode explores the is-ought problem, first exposed by David Hume in his 1739 Treatise of Human Nature, and asks whether it is ever logically possible to derive what we ought to do from what is.

We walk through Hume’s fork and Hume’s guillotine, G.E. Moore’s open question argument, and the slide into moral skepticism and non-cognitivism. Then we test the bridges philosophers have built: Alasdair MacIntyre’s scissors and Arthur Prior’s sea captain, the poisoner dilemma and the unempathetic citizen Alice, G.E.M. Anscombe’s proposal to abandon the moral ought, John Searle’s institutional facts and promises, Philippa Foot’s argument that virtues are as necessary as hands and eyes, the idea of indefinables, and Hilary Putnam’s claim that facts and values are hopelessly entangled.

• The cookbook that ends with “therefore you are morally obligated to bake this cake”
• Why goal-based oughts collapse into relativism
• How a promise smuggles an obligation inside a fact like a Trojan horse
• The historical irony that Hume himself derived oughts from is statements
• A closing question about whether AI trained only on facts can ever learn what it ought to do